Grate structure



Feb. 26, 1935. H. s. LEE 1,992,315

GRATE STRUCTURE Filed May 22, 1951 INVENTOR.

fimzy L as GEM/gm A TTORNEYS.

Patented Feb. 26, 1935 UNITED STATES PATENT OFFICE 'GRATE STRUCTURE Harry s. Lee, Detroit, Mich. f i 7 "Application May 22, 1931, sesame. 539,369

8 Claims. (01.126-167) My invention relates to supporting grates and has particular reference to a grate structure for supportingmaterial being passed through a combustion chamber. 7

a While the invention may be utilized for, various purposes as asupporting grate, I particularly contemplate its use as asupport for red hot cement clinker immediately after its ejection from the burning-kiln. As described in some detail in my copendingflapplication, Serial/No 420,326, filed January 13; 1930, it has been found that cement clinker is vastly improved by subjecting; it to an air draft immediately after it leaves the burn ing kiln. One manner of subjecting the hot clinkerto an air draft at this period is to let it fall directly from the kiln upon a support over which it is moved-by sometype of travelling stoker and directing an.air draft upfrom below the said support through the bed of clinker which has been deposited upon the said support as it is moved thereacross. 1

, An object of ,my invention isto prevent any possible: clogging of thepassages through the support by means of which the airis directed upward- 1y through the clinker bed wherebythe efficiency of this secondary combustion operation might be impaired. i a V w Another object of the invention is to provide a supporting grate structure which, while afford- .ing a substantially'continuous supporting surface across the top thereof, includes means for directing the air draft from below in a forwardly direction corresponding to that in which the hot clinker is being actuated. This arrangement, wherein the air is directed through the clinker "at an angle between the horizontal and vertical, permits the air to contact a maximum amount of clinker, during its upward passage therethrough and at the same time assists in pushing the clinker forwardly along its support.

A further object of the invention is to eliminate to some extent the terrific cutting action of the highly abrasive cement clinker ash: is actuated along the support. By so arranging the supporting grate bars that air passages are provided therethrough over a relatively large portion of its upper surface, what may be regarded as a partial air cushion support is provided which relieves the top surface of the supporting grate somewhat from the-deleterious effect of theabrasive passing thereover.

Other objectsand meritorious-features will be found in the particular combinationand arrangement of parts whereby replacement of the, various units comprisingthe supporting surface as. a

whole may be easily accomplished without interfering with other units, as well as in the simplicity of design which insures cheapness of construction and ease in assembly.

Referring now to the drawing, like numerals refer to like parts throughout the several figures and Fig. 1 is a transverse section of the supporting surface, and

Fig. 2 is an end elevation. 1

through a portion 7 A plurality of supports 10, here illustrated a I-beams of conventional type, are arranged in substantiallyparallel relation at spaced apart intervals along the path over whichthe clinker is to be conveyed. The supporting surface, over whichthe clinkerll is; drawn by some type of chain stoker, is composed of a plurality of supporting; grate; bar assembly units designated broadly by the numeral 12. I I

vlilach unit 12 comprises a plurality of parallel grate bars 14 intermediate the extremities of the unitand a plurality of very similar-yet somewhat differently shaped- -bars 16 at each end thereof.

All of the bars are of the same general form and include lower portions and upper portions which cooperatewhen the bars are positioned as illustrated to form a plurality of tortuous passages l8'which direct an air draft vertically upward through the supporting grate surface and subsequently shift its direction of flow to an angle directed forwardly, as at 20, intermediate the Vertical and horizontal. It is to be noted that the lower portions 22 of the intermediate grate bars 14 depend substantially further across their span than the end bars 16 and that the lower extremities of all of the bars are rounded as at 24 while the upper extremities thereof are flat as at 26 to. form a supporting surface for the clinker. The rounded extremity 24 of the depending portions cuts down theresistance to .the air draft passing upwardly throughthe tortuous passages 18 and it will be noted that the opening at the upvper extremity of the passage is of substantially less area than that at the lower extremity. The rate of change in'the cross sectional areabetween each bar is substantially uniform. Any material bars for this reason. Furthermore, the restriction of the airpassages at their upper extremities will tend somewhat to increase the velocity of the air passing therethrough. e

The extremities of each bar are provided with.

'of grate bars arranged in parallel relation, supwidened flange portions 28 which are adapted to abut one another to maintain the bars properly spaced. Each bar is likewise provided with a projecting portion 30 intermediate its extremities. These are likewise adapted to abut to insure the proper spacing across the entire span of the grate bar assembly.

The lower portions 22 of all the bars are apertured at spaced points to receive the positioning tie rods 32 and 34. These rods are offset at their extremities, as indicated at 36, and adapted to abut one another to maintain the same spacing between the grate bar units as the flanges 28 maintain for each individual bar.

The end bars, the lower portions of which are somewhat shorter than the intermediate bar, are adapted to rest upon the supporting surface provided by the I-beams 10 and the extreme in: termediate bar 14 of each grate bar assembly unit is adapted to abut the extremity of the flange 38 of the said I-beam to position the assembly unit with respect thereto. v l 7 While I have illustrated my improved grate structure as a fixedly positioned assembly supporting material which is pushed thereover by a chain stoker, it will be apparent thatthe same structure may constitute a travelling grate stoker if desired, the advantages of the'grate being inherent in the bar assembly.

Having described a preferred form of my invention, various modifications thereof will be apparent to those skilled in the art and for that reason I intend to limit myself only within the scope of the appended claims. a

WhatIclaimis: U V

l. A grate bar assembly comprising a plurality of grate bars arranged in parallel relation, supporting bars extending transversely of said'grate bars, means on each grate'bar for spacing adja- "cent grate bars, said supporting bars cooperating with the spacing means on said grate bars to maintain said grate bars in position, supporting members for the grate assembly,-said grate bars having portions depending below'said supporting bars, the grate bars adjacent an end of said. supporting bar having their depending portion shorter than the other bars of said plurality of grate bars and being positioned upon one of; said supporting members for the grate bar assembly.

2. A grate'bar assembly comprising a plurality porting bars extending transversely of said grate barameans on each grate bar for spacing adjacent grate bars, said supporting bars cooperating with the spacing 'means on said grate bars to maintain said grate bars in position, supporting members for the grate assembly, said grate bars having portionsclepending below said supporting bars, the grate bars adjacent an end of said supporting bar having their depending portion shorter than the other bars of said plurality of grate bars and being positioned upon one of said supporting members for the grate bar assembly, the

depending portions of certain of the other bars extending belowthe'top of said supporting member and being positioned adpacent thereto to maintain said assembly in position.

3. .A grate bar assembly comprising a plurality of grate bars arranged in parallel relation, supporting bars extending transversely of said grate bars, means on each grate bar for spacing adjacent grate bars, said supporting bars cooperating with the spacing means on said grate bars to maintain said grate bars in position, supporting having portions depending below said supporting bars, the grate bars adjacent an end of said supto said plane and to the lower portions, each grate bar beingzof decreasing thickness from top to bottom providing tapered passageways therebetween, means oneach grate bar for spacing adjacent grate bars, grate bar supportingmembers extending through the lower portions of said grate bars transversely thereof and cooperating with the spacing means on said grate'bars to hold said grate bars in position in said 'assem blies, the ends of said supporting members of one assembly being positionedadjacent the ends of said supporting members of'another assembly to maintain the assemblies in position and to maintain the end grate bars of adjacent assemblies in spaced relation, and means to support said assemblies comprising a beam engaging the bottom of certain grate bars adjacent'the endsof the grate bar supporting members. 7

5. A grate structure comprising'spaced apart supporting beams, 'a plurality of grate bar assemblies carried by said beams, each assembly comprising a plurality of parallel spaced grate bars, means on each grate bar for-spacingradjacent grate'bars, supporting bars extending transversely through said grate bars and cooperating with said spacing means to hold thegratebars in spaced apart relationship, said supporting bars being of a length to extend from the intermediate portion of one beam to the'intermediate portion of the adjacent beam, the grate bars at the end means on each grate bar cooperatingwiththe said rods for holding said grate bars in parallel spaced apart relationship thereon, the grate bars at the end of the rod resting upon the beams, the

grate bars between the beams having a depth greater than thatof the bars which rest upon a the beams, and the grate bar adjacent each beam abutting the beam to hold the assembly'in place.

7. A grate bar assembly comprising a plurality of spaced supporting members, a plurality of grate bars arranged in parallel relationwith one another and with said supporting members, a plurality of supporting bars having a length substantially equal to the distance between. said supporting members extending transversely through said grate bars and above said supporting members to support the grate bars in the spaces intermediate the supporting members,

said grate bars having portions depending below said transverse supporting bars, the grate bars adjacent the ends of the supporting bars having their depending ends shorter than the other grate l bars and being positioned upon the supporting members to support through their depending portions the transverse supporting bars and the grate bars carried by the latterintermediate the supporting members.

8. A grate bar assembly comprising a series of spaced supporting members, a plurality of supporting bars lying transverse to the supporting members and bridging the spaces therebetween, a plurality of grate bars arranged in parallel relation with one another and provided with aligned apertures through which extend the transverse supporting bars, spacer elements on each individual grate bar spacing each grate bar from the other, said grate bars having portions depending below the transverse supporting bars, the grate bars adjacent the ends of the supporting bars having their depending ends shorter than the other grate bars, said supporting members positioned within the recess formed by the shorter grate bars to support the entire grate bar assembly, and the longer depending portion of the grate bars on either side of said recess lying against the side of said supporting members whereby the whole assembly through said spacer elements is compactly held together.

HARRY S. LEE. 

